Process of dyeing cellulose, cotton, or the like



Patented Feb. 23, 1937 PATENT @FFEQ gamer PRQUESS 01F DYEIINGCELLUILUSE, CO'E'JFGN, 0R THE LIKE Arthur Wolfram and Kurt Ronstadt,Frankforton-the-Main,

Germany, assignors to General Aniline Works, line, New York, N. Y., acorporation of Delaware No Drawing. Application February 6, 1935, SerialNo. 5,302. in Germany February 10, 11934 4 Claims.

Our present invention" relates to a process of dyeing cellulose, cottonor the like.

We have found that sulfonic acids of fluorindines are generallydyestufis of a substantive character. -To this group of dyestuffs therebelong, on the one hand, the fluorindine-sulfonim acids which arealready known from the literature (cf., for instance, German Patent78,601) and, on the other hand, those dyestuifs which are obtainableaccording to the process described in our copending application SerialNo. 739,326, filed August 10, 1934. Thus, for instance, the alkali saltsof the sulfonic acids of diarylfiuorindines, obtainable by the processof our said copending application, of the probable general formula:

aryl N\ /N which contain negative groups as, for instance, the nitro-,CO-alkyl-, CO-aryl-, carboxylor the quinone group or polynuclearring-systems, such as the ring system of naphthalene, diphenyl,stilbene, pyrene, anthracene, or both, and which may be halogenated, theRs standing for aryl radicals which may be the same as or different fromthose otherwise present, dye directly cellulose, for, instance, cotton,regenerated cellulose and the like. Thus, there has been found a newgroup of dyestuffs which dye the fiber directly.

The dyestufls may be obtained according to the process of our co-pendingapplication above referred to, for instance, by oxidizing to thefluorindine compound, according to known methods an azophenin compoundof the general formula:

T RI R: N

phenyl is stirred at C. with lpart of the hyparts of para-amino-diLdrochloride of para-amino-diphenyl, and 1 part of para-nitroso-phenol isadded in small portions, so that the temperature remains as constant aspossible. After one hour the whole is allowed to cool to about 70 C. and10 parts of alcohol are then added. The precipitated crystals arefiltered with suction and thoroughly washed with water in order toremove the hydrochloride. The reaction product thus obtained formsred-brown crystals which dissolve in concentrated sulfuric acid to ablue solution.-

One part of the product obtained is dissolved in'30 parts ofnitrobenzene and the solution is heated at boiling temperature forhalf-an-hour with 0.7 part of lead dioxide. solution is filtered whilehot. On cooling, the fiuorindine separates in the form of dark-coloredcrystals which dissolve in concentrated sulfuric acid to a bluesolution. The fluorindine has the following probable formula:

fuming sulfuric acid containing 20% of sulfuric anhydride to act uponthe product, the latter may easily be sulfonated.

parts of cotton are dyed for 1 hour with By causing 3.5 parts of thedyestuff thus sulfonated with addition of 25% of sodium chloride and0.2% of a wetting agent in a proportion of the liquor to.

The blue-violet One part of the product thus obtained is dissolved in 15parts of alpha-chlornaphthalene and the solution is mixed, while hot,with 0.9 part of lead dioxide and boiled for 30 minutes. When thesolution has become blue, it is freed from the .lead oxides byfiltration; on cooling the fluorindine separates in the form of smallcrystals which dissolve in concentrated sulfuric acid to a greensolution. The dyestuff has one of the two constitutions:

By dissolving the fluorindine "1n sulfuric acid monohydrate and addingsuch a quantity of fuming sulfuric acid containing 20% of sulfuricanhydride that the content of S03 of the solution amounts to 5%,sulfonation takes place easily.

100 parts of cotton yarn are dyed for 1 hour with 4 parts of thedyestuff thus sulfonated with addition of 15% of sodium chloride and1.5% of sodium carbonate in a proportion of the liquor to the goods of1:20 and at a temperature of C. to C. A green coloration 'is obtainedwhich is very fast to light.

(3) parts of viscose yarn are dyed for 1 hour with 3 parts of thedyestufi-sulfonic acid used in Example (2) with addition of 20% ofcalcined sodium sulfate and 2% of Marseille soap in a proportion of theliquor to the goods of 1:40 and at a temperature of 85 C. to 90 C. Greendyeings are obtained which have a very good fastness to light.

(4) 100 parts of mercerized cotton fabric are dyed for 1 hour with 5parts of a dyestuif-sulfonicacid which is obtainable according toExample (2), however under stronger sulfonation conditions, while adding15% of sodium chloride and 1.5% of sodium carbonate in a proportion ofthe liquor to the goods of 1:30 at 85 C. to 90 0.. Grey dyeings areobtained.

(5) Instead of the dyestuffs mentioned in Examples 1 to 4 there may alsobe used other dyestuffs which are obtainable according to the process ofour co-pending application above referred to.

We claim:

1. The process which comprises dyeing, according to the methods knownfor substantive dyeings, cellulose material with an alkali salt of asulfonic acid of a fiuorindine compound.

2. The process which comprises dyeing, according to the methods knownfor substantive dyeings, cellulose material with an alkali salt of asulfonic acid of a fiuorindine compound which is obtainable by theprocess which comprises oxidizing to the fluorindine compound accordingto known methods an azophenin compound of the general formula:

wherein R1 represents an aromatic radical containing a negativesubstituent of the group consisting of nitro, CO-alkyl, CO-aryl andcarboxyl, or containing more than one aromatic nucleus or a. quinonenucleus and wherein R2 represents an aromatic hydrocarbon radical, andsulfonating the product thus obtained.

3. The process which comprises dyeing, according to the .methods knownfor substantive dyeings, cellulose material with an alkali salt of asulfonic acid of a fluorindine compound which is obtainable by theprocess which comprises oxidizing'to the fiuorindine compound accordingto known methods an azophenin compound of the formula:

to the fluorindine compound methods an azophenin compound of the andsuifonating the pro according'to known formula:

duct thus obtained. ARTHUR WOIFRAM. KURT BONSTEDT.

